Psy unintentionally brought laughter as he exposed his butt drenched in sweat.

Mnet's "Superstar K4" episode that aired yesterday dispalyed the competition held at an army base.

On this day, Psy became more excited than the contestants and went on the stage. When SISTAR's "Alone" came out, Psy started dancing. His sexy waist dance was impressive, but his butt was drenched in sweat. It had been wet due to hours of sitting during the audition in the hot weather.

At this, all judges including Lee Seung Chul and Son Dam Bi and all the audience members could not hold in their shock.

Photo Credit: Mnet